The Biostatistical Core Unit pursues seven major goals: 1) To provide biostatistical consulting and collaboration to investigators at all stages of the research effort, beginning with aiding in the formalization of hypotheses and design, and ending with interpretation and write-up. 2) To develop, design, and continuously support a large centralized core data base. 3) To develop data management software for rapid, efficient, and highly accurate entry and processing. 4) To develop methods that monitor, correct, and provide feedback on quality control, quality assurance, and reliability at all levels of core data processing including data collection, entry and storage. 5) To provide training on the use of SAS and the core data base. 6) To develop and implement services that help integrate and support research efforts in the MH-CRC. 7) To conduct research in biobehavioral methods and statistical techniques on topics relevant to center research initiatives.